Flex Running

I have never used or owned a fitness tracker. If I’m running, I wear a GPS watch. If I’m biking, I have a bike computer. If I’m doing anything else, well, I can always look at a clock. But Fitbit’s improved ability to track all your activities and stats, and then sync them into one spot was interesting to me.

Two new upgraded Fitbit devices—the Charge 2 and Flex 2—officially launch on Aug. 29, and we got a preview to test them out over the last few days. An upgraded app experience with guided runs, known as Fitbit Adventures, will be coming as well.

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Charge 2

The new Charge 2 ($149) is an update of the Charge HR—so it still has the built-in wrist-based heart rate and automatic activity tracking of steps, calories, elevation, and sleep.

What it’s added is an expanded ability to recognize specific workouts. You can set a handful of activities like running, biking, weights, treadmill, or yoga. Then simply hold down the start button while in that activity screen and press stop when you’re done. If you forget to press start/stop, it automatically recognizes most activities after about 10-15 minutes. This is not a flawless system, but is a nice backup. The Charge 2 also syncs with the GPS in your phone to measure pace and distance—which you are now able to see on the watch screen while working out.